Key Takeaway
Cochrane review found regular vitamin C supplementation reduced cold duration by 8% in adults and 14% in children, but did not prevent colds in the general population.
Summary
Definitive Cochrane systematic review examining vitamin C for common cold prevention and treatment.
Methods
- Cochrane systematic review
- 29 trials with 11,306 participants
- Prevention and treatment studies
- Meta-analysis of outcomes
Key Results
- No prevention benefit in general population
- 8% reduction in cold duration (adults)
- 14% reduction in children
- Greater benefit in physically stressed populations
- Therapeutic use (at cold onset) showed inconsistent results
Figures
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Limitations
- Heterogeneous study designs
- Various vitamin C doses
- Definition of "cold" varied
- Blinding challenges